Point of sale terminals identify items presented for purchase as part of a purchase transaction. A point of sale terminal may suitably use an optical code scanner and weigh scale device to read optical codes on items presented to the terminal for identification and to weigh items that are sold by weight where the weight is determined at the time of purchase.
A frequent fraud that occurs at a point of sale terminal involves identifying an expensive item sold by optical code identification as an inexpensive item sold by weight. This fraud is sometimes called the “Bananas and Bourbon” fraud. The fraud works by placing an expensive item, such as a bottle of bourbon, on the weigh scale of the point of sale terminal. The optical code scanner and weigh scale device senses the presence of the item and starts an item weighing cycle. During the item weighing cycle, optical code identification is disabled. The weigh scale determines a stable weight for the item and sends the stable weight to the point of sale terminal. The point of sale terminal requests that an operator input an identity for the item on the scale. The operator then enters a code that identifies an inexpensive item, such as bananas. The point of sale terminal then calculates the price using the weight of the expensive item and a price per unit weight associated with the inexpensive item identified by the operator. The calculated price is less than the actual price of the expensive item plus the expensive item has been misidentified to the point of sale terminal. This type of fraud not only allows for an expensive item to be sold at a lower price, but may also allow age restricted items to be sold to under age customers.